Pavement grooving apparatus



April 16, 1968 I R. N. ATKINSON 3,

' PAVEMENT GROOVING APPARATUS I Filed Nov. 12, 1965 2 Sheets-Sheet 1 5 RAY N. ATKINSON ATTORNEYS A ril 16, 1968 R. N. ATKINSON PAVEMENT GROOVING APPARATUS 2 Sheets-Sheet 2 Filed Nov. 12, 1965 PIC-3-4 82 INVENTOR.

RAY N. ATKINSON FIG 7 ATTORNEYS United States Patent 3,377,932 PAVEMENT GROOVING APPARATUS Ray Nelson Atkinson, Hillsborough, Califl, assignor to Guy F. Atkinson Company, San Francisco, Calif., a corporation of Nevada Filed Nov. 12, 1965, Ser. No. 507,493 4 Claims. (Cl. 9439) ABSTRACT OF THE DISCLOSURE A pavement grooving apparatus in which a carriage with a rotary grooving knife is carried on a frame spanning the pavement. The knife is driven independently of the frame and the carriage is also propelled along the frame with the grooving wheel rotating to form a groove. The frame also carries knives to form longitudinal grooves in the pavement having notches to allow passing of the transverse grooving wheel.

This invention relates to pavement grooving apparatus.

In the construction of canal linings, roadways, airport runways, and other paved surfaces, it is common to provide expansion joints. These joints are generally in the form of grooves which define weakened planes in the pavement. Stresses due to expansion and contraction, settling and the like will fracture the pavement along these weakened planes.

Grooves have been formed during a paving operation by knives which are moved longitudinally in the wet concrete. Because of their movement along the groove, the knives serve also to trowel or smooth the side surfaces of the groove. In other instances, knives, the length of the groove, are lowered into the wet concrete to form the groove. The sides of the grooves formed in this manner are relatively rough because there is a minimum of troweling action, since the total movement is merely the short vertical movement of the knife as it is inserted and extracted. Another method has been to cut the pavement with a cutting tool after the pavement has set up to form a slot which extends partly or entirely through the pavement.

In the laying of certain pavements, paving machines which receives the paving materials and spread and trowel the material as they move longitudinally along the pavement are employed. Such machines often carry blades which project downwardly into the concrete to form longitudinally grooves as the machine moves along the surface which it is paving. If transverse grooves are required, a blade which extends across the entire Width of the paving machine is projected into the pavement. The transverse groove blade may be carried by the paving machine, or it may be carried on a separate frame which follows closely behind the machine.

It is an object of the present invention to provide an improved pavement grooving apparatus.

It is another object of the present invention to provide a grooving apparatus in which there is a simultaneous grooving and troweling action by a grooving member.

It is another object of the present invention to provide a grooving apparatus including a grooving wheel which "ice It is still a further object of the present invention to provide a grooving apparatus in which a grooving member is carried for positioning longitudinally along the pavement and for movement transverse thereto.

The foregoing and other objects of the invention will become more clearly apparent from the following description when taken in conjunction with the accompanying drawings.

Referring to the drawings:

FIGURE 1 is a perspective View of a grooving apparatusincorporating the present invention;

FIGURE 2 is an enlarged view of a portion of the concrete pavement shown in FIGURE 1;

FIGURE 3 is a sectional view taken along the line 33 of FIGURE 1;

FIGURE 4 is'a sectional view taken generally along the line 4-4 of FIGURE 3;

FIGURE 5 is a side elevation view of a grooving tool, carriage and follower trowels;

FIGURE 6 is a side elevation of a groovingtool, carriage and rails at the end of the grooving apparatus;

FIGURE 7 schematically illustrates a suitable circuit for controlling the solenoid operated follower trowels; and

FIGURE 8 schematically illustrates a circuit for reversibly driving the carriage.

According to the invention, there is provided a grooving Wheel including :a cutting flange. The wheel is rotatably mounted for movement along the paved surface with the cutting flange engaging the pavement. Means are provided for independently rotating the grooving wheel to provide a troweling action between the cutting flange and the pavement. The wheel can be carried for movement along the concrete to form longitudinal grooves or for movement across the concrete to form transverse grooves.

In the embodiment shown, the grooving wheel is carried for movement on a framework adapted to span across a paved surface to form transverse grooves. It is, of course, to be understood that the wheel could be mounted for longitudinal movement as, for example, on the rear of a paving machine to thereby form longitudinal grooves.

Referring generally to FIGURE 1, the apparatus comprises an elongated frame or beam 11 which includes longitudinal members 12 and a plurality of rigidifying diagonal reinforcing members 13. Means are provided for carrying the beam or frame for movement along the pavement 14. Such means is schematically illustrated as a set of wheels 15 disposed at each end of the beam. In the example shown, the transverse groove beam would be towed. It is, of course, apparent that the wheels 15 may be self-propelled to move the apparatus along the pavement 14. A pair of spaced rails 16 are carried at the bottom of the transverse beam. These rails receive wheels 17 of a carriage 18 so that the carriage 18 can be moved longitudinally along the beam.

Referring more specifically to FIGURE 1, the beam is shown straddling the pavement 14. The pavement 14 includes longitudinal grooves 21 formed by a moving blade in the manner previously described. Transverse grooves 22 are formed by the apparatus of the present invention.

Referring more particularly to FIGURES 3, 4 and 5, the carriage 18 carries a motive means 26, such as a motor, which drives a grooving wheel 27 by a belt 28 extending between motor pulley 29 and grooving wheel pulley 31. The motor 26 is mounted on the carriage by conventional means such as pedestal 32. The grooving wheel shaft 33 is journalled for rotation on spaced journals 34- (FIGURE 3). The wheel extends below the lower wall 37 of the carriage and is arranged to that the cutting flange 41 engages the concrete to form a groove while the rims 42 engage the upper surface of the concrete adjacent the groove 22.

The carriage 18 is adapted to travel along spaced rails 16. The carriage is driven along the rails by suitable moving means. Such means may comprise a cable 43 which has its two ends connected by eyes 44 and 46 to opposite ends of the carriage. The cable is adapted to extend over sheaves or pulleys 47 disposed at each end of the beam. The cable is wrapped around the driven pulley 48 which is driven by suitable means, for example, an electric motor or hydraulic motor 49. Rotation of the motor in one direction will drive the carriage along the beam in one direction, while reversal of the motor drives the carriage in the opposite direction.

Referring particularly to FIGURE 1, it is seen that as the carriage 18 is drawn across, the cutting flange 41 will form the groove 22, while the rims 42 will smooth the upper surface adjacent the groove. The groove 22 and smooth upper surface 52 are shown in more detail in FIGURE 2. It is apparent that the configuration of the cutting flange can be selected to form a groove of any desired shape.

When the grooving wheel passes over a longitudinal groove 21, it would upset the side edges of the longitudinal groove and even move material into the longitudinal groove. To prevent this, the carriage 11 carries a longitudinal knife 53 which has a configuration corresponding to the configuration of the previously formed groove 21 which maintains the sides as the grooving wheel crosses the groove. The knife includes a notch 55 for accommodating the cutting flange, as will presently be apparent.

Referring more specifically to FIGURE 3, these knives are carried by a pair of spaced pins 54 which are received by sleeves 56 mounted on the framework. The upper end of each of the pins 54 accommodates a spring 57 and threadably receives a stop nut 58 whereby the spring gives a slight lift to the knife 53 whereby it floats in the longitudinal grooves. When the transverse wheel moves past a knife 53, the wheel engages the knife and firmly seats the knife in the longitudinal groove as it passes across the groove. Thus, the knife 53 holds or maintains the sides of the groove as the transverse groove 22 is formed. The knife 53 may be raised above the surface of the concrete by inserting a spacer (not shown) between the sleeves 56 and the nuts 58. The knife described has a depth which is greater than the depth of the transverse groove. In those instances Where the longitudinal and transverse grooves are of substantially the same depth, the knife may be a two-piece knife with the gap between the two pieces serving to accommodate the cutting flange.

During a grooving operation, the carriage is driven across the beam with the grooving flange 41 forming the transverse groove and the rims smoothing the side surfaces. The wheel is rotated as it moves across the pavement to thereby provide slippage between the wheel and the concrete to give a troweling action. It has been found preferable to rotate the wheel in a direction opposite to the direction the wheel would rotate as it is drawn across the concrete if it were free running. By way of example, with a linear speed of 50 ft. per minute and rotated in the opposite direction at 100 r.p.m. satisfactory grooves have been formed.

If additional troweling or smoothing of the surfaces is desired, following trowels 61 and 62 are provided. The trowels 61 and 62 are mounted on the ends of arms 63 and 64 which are engaged by solenoids 66 and 67 which, when energized, serve to lift the trowel and when deenergized allow the trowel to fall downwardly into the groove to move with the carriage to trowel or smooth the grooves.

The solenoids 66 and 67 may be controlled by a circuit such as that shown in FIGURE 7 wherein the coils 66a and 67a are the coils corresponding of the two solenoids. The coils 66a and 67a are connected to the two poles 66b and 67b of a single pole double throw switch. The switch contact 68 connects either the coils 66a or 67a between the power lines 71 and 72 to thereby energizes the respective coil and solenoid. The switch may be mounted on the carriage, and when the carriage reaches the end of travel in one direction, the switch is switched from one position to the other whereby there is automatic lowering of the followers. It is, of course, apparent that hydraulic rams may be used and controlled through a hydraulic circuit or that mechanical means may be employed.

The drive motor 49 is a reversible motor connected in a circuit such as shown in FIGURE 8 wherein the field winding is represented at 73. The motor may be caused to drive in one or the other direction depending upon the phase of the current flowing therethrough. The motor is connected in circuit with a manual switch 76 which, when closed, will serve to connect the coil to receive the power from lines 77 and 73. A double pole double throw switch 86 is connected between the power lines 77 and 78 and the conductors 81 and 82 which are connected to the field winding 73. It is seen that the phase of the power applied to the winding 73 is reversed by switching the switch from one position to the other. The switch is arranged to be actuated when the carriage reaches the end of its trail to thereby reverse the travel of the carriage. The manual switch 76 is actuated to stop travel. The use of an electric motor is illustrative only. A hydraulic motor could be used for the same purpose.

Means are also provided for lifting the grooving Wheel carriage When the carriage reaches the end of the beam 11. This withdraws the grooving flange from the pavement and permits moving the apparatus to another position. By way of example, the rails are inclined at the end whereby the carriage travels up the incline 86 and onto the raised portion 87 with the wheel above the level of the concrete. Following positioning of the beam, the m0- tor 49 is then energized and the carriage travels the incline 86 and serves to form the transverse groove. When the carriage reaches the opposite ends, it rides up a similar incline 88 and onto the raised portion 89. It is to be understood that other means may be provided for raising the wheel.

Thus, it is seen that there is provided an improved and novel grooving apparatus which includes a rotatable grooving wheel which is independently rotated as it is moved across the pavement to give a troweling or smoothing action. In those instances where additional smoothing is desired, follower trowels are provided. Means are provided for protecting the longitudinal grooves as the transverse groove is being formed.

I claim:

1. Pavement grooving apparatus for forming transverse grooves in pavement which includes longitudinal grooves including an elongated frame adapted to span across said pavement, means for mounting said frame for movement along said pavement, a carriage, means for supporting said carriage from said frame for movement therealong whereby said carriage can be moved back and forth across said pavement, means for reversibly driving said carriage along said frame, a grooving Wheel having a cutting flange adapted to engage said pavement and forming grooves therein rotatably mounted on said carriage with said flange normally engaging said pavement, and knives carried by said frame and extending into said longitudinal grooves, said knives including a notch adapted to receive the cutting flange as the grooving wheel is moved past the same, said knives serving to protect the longitudinal grooves as the transverse grooves are formed by said cutting flange.

2. Pavement grooving apparatus as in claim 1 including means for independently rotating said grooving wheel.

3. Pavement grooving apparatus as in claim 1 wherein said grooving wheel includes a troweling rim on each side of the flange for troweling the upper surface of the pavement adjacent said groove.

4. Pavement grooving apparatus as in claim 1 including a follower trowel mounted for movement with said carriage and adapted to ride in said groove to provide additional traweling.

References Cited UNITED STATES PATENTS 1,718,840 6/ 1929 Thomasson 94-51 1,740,345 12/ 1929 Heltzel 94-45 X 1,963,700 6/1934 Heltzel 9439 2,791,412 5/1957 Hatcher 9439 X JACOB L. NACKENOFF, Primary Examiner. 

